What happened

Classic useSelector in a large app behaves like a building-wide fire alarm: one door click in a single closet can make every resident check whether the alert is theirs. Redux re-runs all mounted selectors on every dispatch. On a small screen that cost is invisible. On a huge subscription tree it is not.

Alpha 9.4 adds an opt-in, signals-based useSignalSelector. The hook records which state fields a selector actually read. The next dispatch re-runs only selectors whose data changed. Everyone else stays asleep. Mark Erikson published the walkthrough; Alpha 1 already landed a bug fix and corrected benchmarks. The signal runtime is a fraction of React’s size, but it has no concurrent rendering, no conventional license yet, and is still experimental.

Also in that React Status issue: Next.js 16.3.6 fixes a critical remote code execution bug in ImageResponse for next/og on Node (v16.2+ affected); nine more fixes are scheduled for the following week. Astro’s React integration hit 7.0, swapping Babel for Oxc and adding a compiler: true option for the React Compiler. Vercel merged its private and open-source bug bounty programs into one public program that covers Next.js.

Why it matters

Selectors are the usual way to keep the whole store out of a component. The habit of “subscribe and forget” collides with growth in subscriber count: every dispatch becomes a tax on the entire UI. A signal selector shifts the model from “check everyone” to “wake only those touched by the change” — closer to how fine-grained reactivity is already discussed outside classic Redux.

For a team with a heavy client store, that is a reason to try the alpha on a staging screen, not to rewrite production tomorrow. Concurrent limits and experimental status matter more than the marketing line “signals in Redux.” The same digest also reminds you that Open Graph holes in Next.js and Astro’s toolchain change are separate urgent topics, not background noise for a selector experiment.

In practice

If selector cost already hurts on frequent actions, read the Alpha explainer and compare useSignalSelector with your current useSelector on one hot screen. Do not mix expectations: this is opt-in and alpha, not a one-release replacement for the whole subscription model.

From the same issue, on security and build:

1. On Node with next/og, upgrade to Next.js 16.3.6 and watch the follow-up vulnerability batch next week.
2. Astro + React: evaluate 7.0 and the Oxc move if Babel is still on your critical build path.
3. Signal selectors only behind an experiment flag and with a measurement on your subscription tree — not “everywhere just in case.”

Takeaway

The headline of the issue is not “signals instead of Redux,” but narrower selector re-runs in 9.4 Alpha. The building no longer has to wake up for every lock click: only the rooms that changed get called. Keep the ImageResponse fix and Astro’s fresh toolchain as separate checklists beside that story.